Electric field directed loading of microwell array

Abstract

An apparatus includes a device substrate including an array of sensors. Each sensor of the array of sensors can include a electrode structure disposed at a surface of the device substrate. The apparatus further includes a wall structure overlying the surface of the device substrate and defining an array of wells at least partially corresponding with the array of sensors. The well structure including an electrode layer and an insulative layer.

What is claimed is: 
     
       1. A method for depositing particles, the method comprising:
 providing a particle suspension to a flow cell of an apparatus, the particle suspension comprising a plurality of particles, the flow cell comprising a counter electrode, the apparatus further comprising:
 a device substrate including an array of sensors, each sensor of the array of sensors including a sensor electrode structure disposed at a surface of the device substrate; and 
 a well structure overlying the surface of the device substrate and defining an array of wells at least partially corresponding with the array of sensors, the well structure including an electrophoretic electrode layer and an insulative layer; 
 
 applying a voltage difference between the counter electrode and the electrophoretic electrode layer, a particle of the plurality of particles depositing in the a well of the array of wells. 
 
     
     
       2. The method of  claim 1 , wherein the particle of the plurality of particles is a charged particle. 
     
     
       3. The method of  claim 1 , wherein the particle of the plurality of particles is conjugated with polynucleotides. 
     
     
       4. The method of  claim 1 , further comprising:
 flowing a nucleotide solution through the flow cell, the nucleotide solution including a nucleotide; and 
 measuring a response to flowing the nucleotide solution with a sensor of the array of sensors. 
 
     
     
       5. The method of  claim 4 , wherein the response is an ionic response proximal to the sensor electrode structure. 
     
     
       6. The method of  claim 4 , wherein the each sensor of the array of sensors is an ion sensitive field effect transistor. 
     
     
       7. The method of  claim 1 , wherein the well of the array of wells is to provide fluid access to a sensor of the array of sensors. 
     
     
       8. The method of  claim 1 , wherein the well of the array of wells exposes the sensor electrode structure of a sensor of the array of sensors. 
     
     
       9. The method of  claim 1 , wherein the electrophoretic electrode layer is exposed in a plurality of wells of the array of wells. 
     
     
       10. The method of  claim 1 , wherein the electrophoretic electrode layer is electrically connected to a plurality of wells of the array of wells. 
     
     
       11. The method of  claim 1 , further comprising an electrical interconnect separate from the array of wells providing electrical access to the electrophoretic electrode layer. 
     
     
       12. The method of  claim 1 , wherein the insulative layer is disposed below the electrophoretic electrode layer and further comprising a second insulative layer disposed above the electrophoretic electrode layer, the array of wells defined through the insulative layer, the electrophoretic electrode layer, and the second insulative layer. 
     
     
       13. The method of  claim 1 , wherein a sensor of the sensor array is an ion sensitive field effect transistor. 
     
     
       14. The method of  claim 1 , wherein the sensor electrode structure includes a floating electrode. 
     
     
       15. The method of  claim 1 , wherein the sensor electrode structure is electrically isolated from the electrophoretic electrode layer except through fluid within the array of wells. 
     
     
       16. The method of  claim 1 , further comprising a cover defining the flow cell over the wall structure, the flow cell to contain a fluid. 
     
     
       17. The method of  claim 16 , wherein the counter electrode is disposed along the cover. 
     
     
       18. The method of  claim 1 , further comprising a voltage source electrically coupled to the electrophoretic electrode layer and the counter electrode. 
     
     
       19. A method for depositing particles, the method comprising:
 providing a particle suspension to a flow cell of an apparatus, the particle suspension comprising a plurality of particles, the flow cell comprising a counter electrode, the apparatus further comprising:
 a device substrate including an array of sensors, each sensor of the array of sensors including a sensor electrode structure disposed at a surface of the device substrate; 
 a well structure overlying the surface of the device substrate and defining an array of wells at least partially corresponding with the array of sensors, the well structure including a first insulative layer, an electrophoretic electrode layer disposed over the first insulative layer, and a second insulative layer disposed over the electrophoretic electrode layer; and 
 a voltage source electrically coupled to the electrophoretic electrode layer and the counter electrode; 
 
 applying a voltage difference between the counter electrode and the electrophoretic electrode layer using the voltage source, a particle of the plurality of particles depositing in the a well of the array of wells. 
 
     
     
       20. The method of  claim 19 , wherein the particle of the plurality of particles is conjugated with polynucleotides, the method further comprising:
 flowing a nucleotide solution through the flow cell, the nucleotide solution including a nucleotide; and 
 measuring a response to flowing the nucleotide solution with a sensor of the array of sensors.